{"cve":"CVE-2026-110871","nvd":{"published":"2026-10-14T23:17:28.953","modified":"2026-10-20T03:17:14.553","status":"Awaiting Analysis","description":"Nodemailer from 3.0.0 before 10.0.10 contains a denial of service vulnerability in MessageParser.parseHeaders that allows users to exhaust CPU through quadratic header unfolding. Attackers can supply large recipient lists or long headers that fold into tens of thousands of continuation lines, blocking the Node.js event loop during DKIM signing.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":7.1},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":6.5},"cwes":["CWE-400"],"references":["https://github.com/nodemailer/nodemailer/security/advisories/GHSA-39m8-27wv-hr27","https://www.vulncheck.com/advisories/nodemailer-3.0.0-before-10.0.10-quadratic-dkim-header-unfolding-denial-of-service","https://github.com/nodemailer/nodemailer/security/advisories/GHSA-39m8-27wv-hr27"],"products":[],"source":"nvd","synced_at":"2026-10-21T03:56:58.798400159+00:00"},"epss":{"cve":"CVE-2026-110871","score":0.00381,"percentile":0.31775,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-39m8-27wv-hr27","url":"https://osv.dev/vulnerability/GHSA-39m8-27wv-hr27","summary":"Nodemailer: Quadratic (O(n^2)) DKIM header unfolding lets a large folded header cause remote denial of service during signing","modified":"2026-10-22T16:15:47.127282008Z","packages":[{"ecosystem":"npm","name":"nodemailer","purl":"pkg:npm/nodemailer","ranges":[">=3.0.0 <10.0.10"],"fixed":["10.0.10"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}